MORPHOLOGICAL FEATURES OF STRUCTURES REGULATING HEMOCIRCULATION IN THE INTESTINAL WALL

The coefficient of capillary filtration in the intestine is very high and almost 30 times higher than in the capillaries of skeletal muscles. Therefore, with a decrease in capillary pressure, the volume of liquid in the intestine will rapidly decreases, especially quickly this happens with a decrease in systemic blood pressure.Purpose: to identify morphological structures that regulate hemocirculation in the intestinal wall.Material and methods:. The study was conducted on infertile dogs (n=9) of both sexes. Anesthesia - sodium thiopental intraperitoneally (50 ml/kg). Bloodletting from one femoral artery continued until blood pressure in the other femoral artery decreased to60-70 mm Hg. After that, a median laparotomy was performed. A polyethylene tube was inserted into the first jejunal artery, which advanced to the main trunk of the superior mesenteric artery. Portal vein catheterization was performed through the first jejunalvein. The intraorganic blood bed of the intestine was impregnated with a weak solution of silver nitrate and then restored to metal on the walls of microvessels with a 4% hydroquinone solution. After 10 days of fixation, paraffin sections were prepared from the intestinal wall. Sections 3.0-5.0 μm thick were stained with hematoxylin and eosin, according to Van Gison, pararosanilin and toluidine blue, Weigert iron hematoxylin. Results and discussion. When studying histological injected drugs, the most significant changes in the microvascular channel were found in the wall of those areas of the intestine whose blood supply was carried out from zones of adjacent blood flow. In them, signs of impaired vascular permeability were determined in the submucosa. The diameter of a significant number of arterioles decreased so sharply throughout that it indicated the cessation of blood flow in them. The diameter of the venules decreased fragmentary with a uniform alternation of sections of narrows resembling a peristaltic wave. If microvascular bed perfusion of intestinal wall is disturbed, blood flow rate in superior mesenteric artery decreases and internal diameter of its main trunk decreases.Conclusions. The intestine is the most resistant of all internal organs to ischemia. After bleeding from the femoral artery, themost significant changes in the microvascular channel were found in the wall of those areas of the intestine whose blood supply was carried out from areas of adjacent blood flow.

intestine, hemocirculation in the intestinal wall, superior mesenteric artery, disorder of the vascular permeability

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